Studies have shown that exercise greatly reduces the risk of heart disease and other ailments, and also contributes to better overall health and well being. Weight lifting has been determined to be a very important part of a well balanced exercise regimen. Accordingly, people are joining health clubs and purchasing home gym equipment in order to improve their physical fitness.
Health clubs typically have several racks of non-stackable dumbbells of varying weight which range from five pounds to approximately 120 pounds in five-pound or similar increments. The racks to hold all of the dumbbells in the five-pound to 120-pound sets are typically several feet long. Because such sets of dumbbells are extremely expensive and consume a lot of space, these sets are not well designed for home use.
Dumbbells have been designed for home gym use to include a bar having a center sleeve portion which defines a handle and weight discs which are removably attached to each end of the bar by a locking collar. A problem with these prior art designs is that it is still necessary to maintain a full set of disc weights which can be placed on the ends of the dumbbell bar. Furthermore, it is time consuming to put the weights on and take the weights off from this type of dumbbell design. The locking collars are also a safety hazard if they are not properly secured in place. In addition, with the weights being disposed at each end of the dumbbell, the moment arm which is applied to a user's wrist if the dumbbell is not maintained in a horizontal plane can result in painful stresses to the wrist joint of the user. Similar painful stresses are present with standard one-piece dumbbells.